1.People who pretend to be something they're not because they think it makes them realy cool when in actual fact it makes them look like desperate wannabe's who can't get friends any other way (which is what they are).
2.Also when people pretend to like, for instance, a band when actauly they just think the lead singer is 'hot' as opposed to actualy liking the music.
Poser: OMG i sooooooooooo love mcr! They are like my favourite band.
Non-poser: Realy? same, i realy like their music. My favourite song is probably 'You know what they do to guys like u in prison'. Whats yours?
Poser: ummm...uh...i dunno but Gerard Way is waaaaay hot!
(btw im not saying mcr are not hot im just saying that thats the ONLY reason the posers will like the band, because they think they're hot.)